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Steam fires underwater jet engine

By Ben Crystall

A REVOLUTIONARY new steam engine, described by its inventors as “an underwater jet engine”, may soon be powering dinghies and speedboats more efficiently, cleanly and safely than a conventional outboard motor.

The Pursuit Marine Drive produces thrust by using the energy from high-pressure steam to draw in water through an intake at the front and expel it at high speed through the rear. The steam emerges at high speed from a rearward-facing ring-shaped nozzle into a cone-shaped chamber, where it mixes with the water (see Graphic). Shock waves created as the steam condenses are focused by …